[HTML] Add some debug traces.
[HTML] Handle also DIID_DWebBrowserEvents and DIID_DWebBrowserEvents2 in QueryInterface()
[HTML] Revert "Use proper reference counting instead of a dummy one."

This reverts commit e6169598bc066d83db79122dc8f34776b789fb5b.

The proper ref. counting was buggy and caused too early freeing of the
html_t when accessing some URLs, e.g. "https://sourcerorge.net".